/in/foo.c: In function 'main':
/in/foo.c:16:7: warning: variable 'ch' set but not used [-Wunused-but-set-variable]
  char ch='i';
       ^~
/in/foo.c: In function 'A':
/in/foo.c:74:3: error: stray '`' in program
  {`
   ^